Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc5b0b40a0fc09bd…

MALICIOUS

PDF

79.0 KB Created: 2021-09-08 18:05:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7257a5f86a6597f9e6eeb98e58d9ac09 SHA-1: 53f0c03db5ac5f04ac91fa3ba387dcca8976de02 SHA-256: dc5b0b40a0fc09bd940981968a19022898f0cef4601694dbff796458d50045f1
116 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on potentially compromised websites or disposable hosting. The ML classifier strongly indicates maliciousness, and the presence of a raw IP address in a URI further supports this. The document's purpose appears to be to lure users into downloading and opening these linked PDFs, likely as part of a larger malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://211.129.1.225/system/ckfinder/userfiles/files/1690257356.pdf PDF link annotation
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613524aec1774---11028092748.pdfIn PDF document text
    • https://sausalito.com/wysiwygfiles/file/53722435605.pdfIn PDF document text
    • https://nicklason.se/ckfinder/userfiles/files/fovufilor.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/i8j91l3uk49f342c7vmt9p6ndn/43653471664.pdfIn PDF document text
    • http://ultraljud.nu/bild/files/girudu.pdfIn PDF document text
    • http://ketnoikienthuc.com/upload/files/ridufesekipusufuz.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/16521706428.pdfIn PDF document text
    • http://bowie.abwingsmd.com/uploads/files/fejabax.pdfIn PDF document text
    • http://sunnyten.net/userData/board/file/xilamalo.pdfIn PDF document text
    • http://pjteam.hu/uploads/netewogagu.pdfIn PDF document text
    • https://optical-axis.com/uploads/files/202109071609334980.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/72361831996.pdfIn PDF document text
    • http://shqinze.net/admin/upimg/file///8626505034.pdfIn PDF document text
    • http://fueandhair.com/userfiles/files/dibak.pdfIn PDF document text
    • http://thebeautyofdesign.nl/ckfinder/userfiles/files/56262221438.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/65c10469a7dac419beca10ca152cedb7/rojirogabusasupatubasasuk.pdfIn PDF document text
    • https://mytekas.com/UserFiles/file/20612929901.pdfIn PDF document text
    • https://alhasooncorp.com/Files/files/853907590.pdfIn PDF document text
    • http://naosgym.com/userfiles/files/68476840719.pdfIn PDF document text
    • http://kondicionery-pushkino.ru/upload_picture/file/64168301944.pdfIn PDF document text
    • https://arabadvertise.com/userfiles/files/861038852.pdfIn PDF document text
    • http://scarpatti.com/files/tinojumedeweje.pdfIn PDF document text
    • https://mangalargalux.com.br/ckfinder/userfiles/files/jetebiralobu.pdfIn PDF document text
    • http://ykzn8.com/upfiles/editor/files/61379722036.pdfIn PDF document text
    • http://sarkar.ie/userfiles/file/78784281931.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=sistema+oseo+en+ingles+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cc0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC0C 18680 bytes
SHA-256: 0e7f267ad87e7233ad698e33e9740a80ad950b3fc780f00dd94ca45fd1481513
font_01_sfnt_off0000fbb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBB9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000113d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113D0 10816 bytes
SHA-256: fd1d7ef82d56961222a652aa5f861b1443a733c7c83dd180ad43837c5bafe538